Process of reducing metallic oxids.



UNITED STATES PATENT OFFICE.

EDGAR F. PRICE AND FREDERICK M. BECKET, Ol" NIAGARA FALLS, NEW YORh, ASSIGNURS, BY MESNE ASSIGNMENTS, TO CENTRAL TRUST COMPANY OF NEW YORK, TRUS'IICII, A

CORPORATION OF NEW YORK.

Specification of Letters Patent.

Patented June 23, 1908.

' Application filed August 5, 1907. Serial No. 387,241.

T 0 all-wh0m it may concern:

Beit known that we, EDGAR F. PRICE, citizen of the United.States, and FREDERICK M. BECKET, subject of the Kin of Great Britain, residing at Niagara Falls, in the county of Niagara and State'of New York, have invented certain new and useful Imrovements in Processes of Reducing Metal- 'c Oxids, of which the following is a specification.

This invention is a process of reducing metallic oxids, oxid mixtures or oxygen-containing compounds, by reacting thereon simultaneously with'baseand acidforming reducing agents. may comprise two, carbids, the non-carbon elements of which are capable of entering together into a slag of suitable composition,"

thus the'reducing a ent may consist of a mixture'of'cai bids of si 'conand calcium in such proportions that the silica and lime produced may unite'to yield a silicate slag of suitable character. Or instead oftwo carbids, a base-forming reducing agent, such as calcium carbid, may be used in conjunction with an acid-forming reducing agent such as metallic silicon or angalloy containing the same. Ifdesired carbon in the form of coke or otherwise may be used in conjunction with the carbids, or with the mixture of carbid or base-forming reducing agent and silicon.

The process is advantageously applied to.

the reduction of oxids or oxid mixtures containing the refractory metals chromium,

tungsten, molybdenum, and vanadium. The

proportions of the respective carbids in the reducing agent will depend to some extent upon the pres'encor absence of acid or basic slag-forming ingredients in the ore to be reduced, the reducing agent being compounded to yield in all cases asuitable slag. The process is applicable to the production of the refractory metals above mentioned or to alloys of these with iron, nickel or other metals, and presents particular advantages for the preparation of products low in carbon, for which purpose an electric furnace .is employed. The rocess will be described by way of examp e by reference to the production of lowcarbon ferro-chromium by reduction of chromite or chrome iron ore by means of calcium and silicon carbid but the invention is not restricted thereto.

The'chrome iron ore in a suitable state of The reducing agentsubdivision is commingled with a reducing agent containing carbid of calcium and carbld. of silicon, and the mixture is then fused in a suitable electric furnace, usually provided with carbon or" graphite electrodes and a hearth or lining'of a refractory material other than carbon, such as chromite. The combined carbids may be used in proportion to unite'with the oxygen ofthe reducible oxids of the ore, both the carbon and the noncarbon elements of the carbids entering into the reaction. -For instance one specific equation'represnting the process might be expressed as follows:

3FeOOr,O ZCaC, 28K) Many commercial chromites contain both alumina and magnesia, and in such case the proportion of calcium carbid in the reducing agent would-usually be lessened, the object in all cases being to secure economical working conditions by the provision of a slag of suitable composition. In the case of siliceous ores, a small proportion of silicon carbid would usually be required. As will be obvious, the character of the slag may be controlled-not only by varying the composition of the reducing agent, but also in the usual manner by the addition of a suitable proportion of abasic or acid flux asmay be required. Other carbids of baseor acidforming elements might of course be substituted for those of calcium and silicon should this be desirable. In the case of siliceous ores, both constituent carbids of the reducing agent may be of base-forming elements, as for instance carbids of calcium and aluminum; in such case the lime and alumina resulting from the reduction will unite with the silica of the ore toproduce a fusible silicate slag.

For the production of iron ornickel alloys having, any desired content of chromium or other refractory metal ,iron or nickel or compounds of these metals may be incorporated with the mixture tobe reduced or added to the bath. The process is preferably rendered continuous by adding fresh portions of the charge as required and withdrawing. the products from time totime.

The word silicon as employed in certain of the claims is intended to cover generically the use of this element in a reacting state,

which consists in smelting a char e containa metallic oxid and carbids 0 baseand acidforming elements in proportion to yield a suitable slag. 1

4. The process of reducing oxid ores which consists in smelting a charge containing an I v which 'consists in mixin oxid ore and carbids of baseand'acidforming elements in pro ortion to yield a suitab e slag with'the s ag-forming constituents of the ore.

5. The process of reducin metallic oxids which consists in reacting t ereon simulta- Iegusly with calcium carbid and silicon car- 6. The process of reducing metallic oxids which consists in reacting thereon simultaneously with calcium carbid and silicon carbid in pro ortion to yield a suitable slag.

7. he process of reducing metallic oxids which consists in reacting thereon simultaneously with calcium carbid and silicon carbid in proportion to yield a suitable slag with the slag-forming constituents ofthe ore.

8. The process of reducing metallic oxids which consists in mixing therewith a reducing agent com rising a plurality of carbids and smelting t e mixture in an-electric furnace.

9. The process of reducing metallic oxids therewith a reducing) agent comprising a p urality of carbids in su stantially the proportion required for combinin with the oxygen of the ore, and smelting t e mixture in an electric furnace.

10. The process of reducing metallic oxids which consists in mixing therewith a reducing agent comprising carbids of calcium and sihcon, and smelting the mixture in an electric furnace.

1]. The process of reducing metallic oxids which OOIISIStS in mixing therewitha reducing agent comprising carbids ofcalcium and sihcon in substantially the proportion" required for combining with the oxygen of the ore,- and smelting the mixture in an electric furnace.

12. The process of reducing metallic oxids which conslsts in mixing therewith a reducing agent comprising carbids of calcium and sihcon in the'relative proportion required to yield a suitable slag, and smelting the mixture in an electric furnace.

13. The rocess of producing ferro-chro-v mium which consists in reacting on chromite in an electric furnace with carbids of calcium and silicon.

14. The rocess of producing ferro-chromium which consists in reacting on chromite in an electric furnace with carbids of calcium alnd silicon in proportion to yield a suitable s a 1 5. The process of reducing metallic oxids which consists in reacting thereon with amixture of a base-formin carbid and a material containing unoxidize silicon.

16. The process of reducing metallic oxids which consists in reacting thereon simultaneously with calcium carbid and a material con tainin unoxidized silicon.

17. he process of reducing metallic oxids which conslsts in reacting thereon simultaneously with carbon and with base-forming and acid-forming reducing agents.

In testimony whereof, we affix our signatures in presence of two witnesses.

EDGAR F. PRICE. FREDERICK M. BECKET. Witnesses:

C. C. MOSHER, J. N. DEINHARDT. 

